In a process for manufacturing rounded pieces of food dough having a viscosity, as, for instance, that of bread dough, a sequence in which kneaded food dough is divided into predetermined quantities, and then each divided food-dough piece is rounded, is proposed. The food-dough pieces such as the bread dough fed from a rounding machine is manually divided into predetermined quantities or divided by any well-known divider. As for the divided food-dough pieces, the shapes are uneven, and the cutting surfaces have an adhesiveness, and thus firmer skin is not formed.
The purposes of the rounding process are equalizing the food-dough pieces in a specific shape, forming firmer skins of the food-dough pieces, equalizing inner layers of the food-dough pieces, and so on. To round the food-dough pieces, it is known that the rounding process can be efficiently performed by dispersing projections and corners on the surfaces of the food-dough pieces in an early stage to round the food-dough pieces such that each entire piece forms a roundish shape and thereafter forms a uniform shape with a firm skin.
Conventionally, there is a rounding machine that is provided with a pair of movable guiding plates in which the respective plates are opposed to each other, such that they approach, and retract from, each other, above a base or above a conveying platform (a conveying device) for supporting and conveying divided food-dough pieces. In this machine, while the respective food-dough pieces are pressed between the opposed guiding plates when they are close to each other, the dough pieces are rolled horizontally on the conveying surface and rounded by having the guiding plates swing in opposite directions, as is, for instance, disclosed in Patent Literature 1 and 2.
Further, in this conventional rounding machine, the paired guiding plates are positioned to incline outwardly from the lower side to the upper side thereof such that the distance between the opposed guiding plates is narrower at the lower side and wider at the upper side. For the respective guiding plates, the angle of installation therebetween and the distance between the installation points can be adjusted such that an angle therebetween may be smaller when the predetermined quantity of each divided dough piece is smaller, while it may be larger when the predetermined quantity of each divided dough piece is larger.